DE 36 36 243 A1 is concerned with such a collar. The wheel bearing unit, generally an angular ball bearing arrangement or angular roller arrangement, is held free of play in a prestressed fashion by means of the collar. The finished collar 3 according to FIG. 1 is, as illustrated in FIG. 2a and FIG. 3, shaped from a hollow end piece 2 which is formed in one piece with a hub 1. When the collar 3 is formed, the material of the end piece 2 is turned-over plastically over the edge 4 of the inner ring 5 radially toward the outside. If the collar 3, as also illustrated in FIG. 2b, has an end toothing 6 with teeth 7 for engagement in a mating toothing (not illustrated in more detail), the teeth 7 are either also formed when the end piece 2 is placed around to form the collar 3 or the teeth 7 are formed in the finished collar 3 with a separate method step. The mating toothing is formed, for example, on a bell of a cardan shaft.
The collar 3 is shaped with a tool from the end piece 2. For this purpose, the end piece 2 which is initially essentially hollow-cylindrical, as illustrated in FIG. 3, is widened in a radial funnel shape and is shaped in the end position according to FIG. 2b to form the collar 3. The formation of the teeth 7 is problematic. The material of the part 8 of the end piece 2 tapers during the widening and turning-over process and flows radially outward. The respective tooth 7 is not fully formed toward the outside owing to the uncontrollable flowing away of the material, and the loadbearing component, which is determined in particular by the dimension B, is small. B is a line segment between the points S and T. The component C and A−(B+C) which is not filled in here is small measured in terms of the overall proportion of the tooth 7 over the length A.
Also, a portion of the material under certain circumstances moves toward the inside in an uncontrolled way so that an annular gap 31 is formed between the inner ring 5 and the hub 1 and has a disadvantageous effect on the fixed seat of the inner ring 5.
Specialists in the field have attempted to prevent this problem by means of a tool, as presented in DE 36 36 243 A1 which prevents the collar from flowing away radially on the outside. However, the process is generally difficult to implement with the necessary quality owing to tolerances in the dimensions of the blank such as the wall thickness and diameter of the end piece.
During the mounting of the drive element in the wheel hub arrangement, the drive element and the wheel hub center themselves relative to the rotational axis owing to the geometry of the toothing with respect to one another. A high degree of true running on the connection in the driving mode is thus secured. The mounting of the articulated part with respect to the hub is easy owing to the self-centering but it requires a very high axial prestressing force.
The edges of all the teeth of the end toothing engage with both edges of all the teeth of the mating toothing. The toothings are braced axially by means of one or more screw elements. Torques are transmitted to the wheel hub by the frictional engagement/positive engagement generated by surface pressure.
The connection of the articulated part to a wheel hub is advantageous in particular if high torques are to be transmitted from the drive to the wheel or, under certain circumstances, also in the reversed torque flow. The possibilities in terms of installation space and thus in terms of the rigidity of the pairs of inner toothings and outer toothings which are generally used are often already exploited to the full so that the end toothing is, compared to the latter, a reliable alternative which provides a saving in terms of installation space. The rigid configuration for transmitting high torques to the wheel can have a disadvantageous effect if, in the case of overloading, a fracture in the wheel hub leads to loss of the vehicle wheel in the most unfavorable case.